<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
	</head>
	<body>
		<select onchange="run1()">
			<option value="sh">上海</option>
			<option value="bj">北京</option>
			<option value="js">江苏</option>
		</select>
		
		
		
		<script>
			// 域内容改变
			function run1(){
				alert("值改变啦")
			}
		
		</script>
	</body>
</html>
